Effect of growth hormone and 17beta-oestradiol treatment on metabolism and body composition in girls with Turner syndrome

The Interplay between Muscular Grip Strength and Bone Mineral Density with Consideration of Metabolic and Endocrine Parameters in Individuals with Turner Syndrome

INTRODUCTION

Patients with Turner syndrome (TS) often face skeletal and muscular challenges, including reduced bone mineral density (BMD) and muscle weakness. This comprehensive study sheds light on the complex interplay between muscle strength, BMD, and metabolic and endocrine parameters in TS and healthy subjects.

METHODS

A cross-sectional study involving 42 TS patients and 70 healthy women was conducted. All patients had their BMD determined in the L1-L4 lumbar spine section and in the whole skeleton as well as the parameters of body fat mass (BF), and visceral fat mass (VF) were also determined. The maximum gripping force was measured with a hydraulic manual dynamometer. In addition, a number of blood hormonal and metabolic parameters were determined.

RESULTS

In the TS group, hand grip strength correlated positively with triglyceride levels but not with BMD. Healthy individuals had a positive link between hand grip strength and BMD, while patients with TS did not show a significant association between the two. A trend suggested that longer recombinant human growth hormone (rhGH) therapy might improve BMD in the L1-L4 region. Multiple linear regression analysis revealed that muscle strength assessment may be a potential exponent of reduced BMD, and also used clinically in young adult women but not in individuals with TS.

CONCLUSIONS

The relationship between BMD variables and hand grip might differ between the two groups, potentially indicating distinct musculoskeletal characteristics in TS patients. Longer rhGH therapy in TS patients may have a positive effect on BMD in the L1-L4 region. Understanding the intricate relationships between these factors is important for optimizing clinical management strategies and improving the quality of life for TS patients.

Prevalence and Predictors of Prediabetes in Adolescents and Young Adults with Turner Syndrome: A Cross-Sectional Study from Eastern India

Background

Individuals with Turner syndrome (TS) have a high risk for prediabetes/type 2 Diabetes Mellitus (T2DM). There is scarce data regarding risk factors for prediabetes in TS, specially from South Asia.

Methods

We conducted a cross-sectional study on girls with TS aged 12-30 years who had achieved pubertal stage B3 and above-spontaneously or with oestrogen. Anthropometric measurements and biochemical tests were conducted, and medical records were reviewed for details about pubertal onset and progression, growth hormone (GH) and oestrogen therapy.

Results

Out of 129 patients with TS in our database, 99 met the criteria for inclusion, mean age 18.33+/-3.78 years and mean BMI 20.57+/- 3.71 kg/m2. Prevalence of prediabetes was 23.23%. Plasma-glucose measured after 75 g-oral-anhydrous-glucose-load (OGTT-PPG) identified five additional prediabetes cases, who had normal fasting plasma glucose (FPG) or HbA1c%. Compared to those without prediabetes, TS with prediabetes (n = 23) had higher mean body weight, BMI, waist circumference (WC) [42.02+/- 5.83 vs 36.22+/-8.07, 22.77+/-2.78 vs 19.91+/- 3.72, 85.26+/- 3.52 vs 81.08+/- 4.59, pall < 0.03 ], higher median WC-to-height ratio (WHtR) and WC-to-hip ratio (WHR)((0.64 [0.6-0.69] vs 0.59[0.56- 0.66], 0.9[0.84-1.12] vs 0.85[0.75-1.01], pboth < 0.02), and higher LDL-cholesterol, triglycerides, and greater prevalence of hepatosteatosis (47.1% vs 21.1%, P < 0.01). Among GH recipients (n = 36), those with prediabetes had delayed initiation and shorter duration of GH therapy. There were no differences in cardiometabolic parameters or the prevalence of diabetes between different karyotypic variants of TS. BMI, WC and WHR had significant positive correlation with FBG, OGTT-PPG and HbA1c% (pall < 0.004). Delay in oestrogen initiation had a significant correlation with OGTT-PPG (Spearman's-rho = 0.69, P < 0.004). BMI, WHR and pubertal status were independent predictors for prediabetes (OR: 1.27 [1.03-1.57]), 1.18 [1.04-1.34]) and 0.09[0.02-0.38], respectively, pall < 0.02), but karyotype was not. BMI had the highest sensitivity [cut-off: 21.04 kg/m2 (sensitivity: 82.6%, specificity: 62.2%) and WHR had the highest specificity [cut-off: 0.89 (sensitivity: 73.9%, specificity 78.4%)] for predicting prediabetes.

Conclusion

Indian girls with TS have a high risk for prediabetes, irrespective of underlying karyotype and should be screened with oral glucose challenge to identify prediabetes. Timely intervention against central obesity and early initiation of GH and oestrogen should be ensured in TS. Late presenting girls should be closely monitored for dysglycaemia before and during treatment with GH and/or oestrogen.

Normal bone density but altered geometry in girls with Turner syndrome

OBJECTIVES

Data on bone density and stability in Turner syndrome (TS) are contradictory. A confounding factor for interpretation is short stature. The aim was to measure bone density, geometry and stability in girls with TS compared to idiopathic short stature (ISS).

METHODS

From 1999 to 2008, 59 girls with TS (35 prepubertal) were evaluated by pQCT. Mean age was 8.9 in prepubertal and 17.3 years in adolescent girls. Mean height was -3.1 and -1.8 SDS in prepubertal treatment-free and in adolescent, formerly rhGH-treated girls. For comparison, 18 prepubertal ISS girls were studied (age 7.7 years; height -3.3 SDS). Examination of radius with pQCT (XCT 2000). Cortical (CD) and trabecular density (TD), total bone area (TBA), cortical area (CA), cortical thickness, muscle area and strength strain index (SSI) were determined and compared with height related references.

RESULTS

In prepubertal girls with TS, TD and CD were normal (0.55 and 0.90 SDS) and comparable to ISS (0.95 and 1.53 SDS). TBA was greater in girls with TS than in ISS (0.87 vs. -0.33 SDS) whereas CA was similar (1.48 vs. 1.43 SDS). The SSI was comparable (1.61 vs. 1.56 SDS). Adolescent girls with TS showed similar results with a TD of 0.48 SDS, a CD of -0.32, TBA of 1.99, a CA of -0.05 and an SSI of 0.88 SDS.

CONCLUSIONS

The observations are consistent with normal bone density and stability but altered bone geometry in prepubertal and substituted adolescent girls with TS. This peculiarity may reflect SHOX deficiency. We therefore think that timely and adequate estrogen substitution could prevent bone loss in TS.

Hyperglycemia in Turner syndrome: Impact, mechanisms, and areas for future research

Turner syndrome (TS) is a common chromosomal disorder resulting from complete or partial absence of the second sex chromosome. Hyperglycemia, ranging from impaired glucose tolerance (IGT) to diabetes mellitus (DM), is common in TS. DM in individuals with TS is associated with an 11-fold excess in mortality. The reasons for the high prevalence of hyperglycemia in TS are not well understood even though this aspect of TS was initially reported almost 60 years ago. Karyotype, as a proxy for X chromosome (Xchr) gene dosage, has been associated with DM risk in TS - however, no specific Xchr genes or loci have been implicated in the TS hyperglycemia phenotype. The molecular genetic study of TS-related phenotypes is hampered by inability to design analyses based on familial segregation, as TS is a non-heritable genetic disorder. Mechanistic studies are confounded by a lack of adequate TS animal models, small and heterogenous study populations, and the use of medications that alter carbohydrate metabolism in the management of TS. This review summarizes and assesses existing data related to the physiological and genetic mechanisms hypothesized to underlie hyperglycemia in TS, concluding that insulin deficiency is an early defect intrinsic to TS that results in hyperglycemia. Diagnostic criteria and therapeutic options for treatment of hyperglycemia in TS are presented, while emphasizing the pitfalls and complexities of studying glucose metabolism and diagnosing hyperglycemia in the TS population.

Isochromosome Xq and the risk of metabolic comorbidities in Turner syndrome

BACKGROUND AND AIM

Subjects with Turner syndrome (TS) are at increased risk of metabolic disorders. The objective of this study is to evaluate the prevalence of metabolic abnormalities in TS and compare the metabolic profiles of subjects with respect to their X chromosome dosage.

METHODS

Sixty-four TS subjects with a mean age of 19 ± 4.9 years were included, and the prevalence of metabolic abnormalities was assessed. Out of these, 54 age and body mass index-matched TS subjects were divided into two groups based on karyotype: 45,X and 45,X/46,XX (group I; n = 33) and 46,X,i(X)(q10) and 45,X/46,X,i(X)(q10) (group II; n = 21). They were compared for blood pressure, fasting plasma glucose, homeostasis model assessment (HOMA) of insulin resistance (IR) and β cell function (HOMA-β), lipid profile, and percent total body fat mass (PTBFM) to assess if an extra copy of Xq contributes to a different metabolic profile.

RESULTS

The prevalence of impaired fasting glucose was 7.8%. 12% of subjects had higher systolic blood pressure (SBP), and 16% had higher diastolic blood pressure for age. 53% had a deranged lipid profile. Significant differences were noted in the two groups, with higher prevalence in group II vs. group I for SBP (p = 0.03), low-density lipoprotein cholesterol (LDL-c) (p = 0.03), and PTBFM (p = 0.02). When we applied a multiple regression analysis for these outcome variables while adjusting for potential confounders known to influence the cardiometabolic risk profile in TS, karyotype no longer remained a significant independent variable.

CONCLUSION

Extra copies of Xq do not contribute to an adverse metabolic risk profile.

Histopathological and immunohistochemical changes of the marginal periodontium in patients with Turner syndrome

Turner syndrome (TS) is characterized by partial or complete loss of a sexual chromosome, resulting in an incomplete development of the body, gonadic failure, cardiac and renal abnormalities, oro-dental changes, etc. In our study, we proposed to perform a histological and immunohistochemical (IHC) study of the periodontium changes in patients with TS. The biological material under study was represented by fragments of gingival mucosa harvested from 18 patients with TS who presented advanced periodontal lesions and required dental extractions. The fragments of gingival mucosa were processed by the classical histological technique of paraffin inclusion, subsequently the obtained sections being stained by the Hematoxylin–Eosin (HE) and examined under the optical microscope. For the IHC study, there were performed serial sections incubated with anti-cluster of differentiation (CD) 3, anti-CD20 and anti-CD68 antibodies for highlighting immune cells, as well as with anti-matrix metalloproteinase (MMP) 2 and anti-MMP8 antibodies for highlighting MMPs (MMP2 and MMP8) involved in the periodontal tissue lesions. In the present study, during the histological examination, there were observed morphological changes, both in the epithelium and in the gingival mucosa chorion. Epithelial changes consisted in the onset of acanthosis processes, in the thickening of the epithelium due to the increase of the spinous layer, as well as in the parakeratosis phenomenon. In the chorion, there was observed the presence of inflammatory infiltrates in various stages, presence of fibrosis (extended in some cases) and the presence of an important vascularization in some cases, with a high number of immunocompetent cells involved in the inborn immune response, but also in the adaptive one, as well as a more or less intense immunoexpression of MMP2 and MMP8. Our study suggests that TS may contribute to the development of some inflammatory processes in the marginal periodontium.

Turner syndrome and osteoporosis

Turner syndrome is one of the most common sex chromosomal anomalies, characterized by the complete or partial loss of one X chromosome. Females with Turner syndrome are characterized by skeletal abnormalities, short stature and primary ovarian insufficiency. The aim of this narrative review was to identify the underlying mechanisms of osteoporosis in Turner syndrome, summarize its clinical manifestations and provide suggestions regarding the management of osteoporosis. Girls and women with Turner syndrome have lower bone mineral density and a higher fracture rate than healthy individuals. The most important risk factors for osteoporosis are inadequately treated primary ovarian insufficiency, followed by intrinsic bone abnormalities. Comorbidities that further increase the risk of osteoporosis include vitamin D deficiency, celiac disease and inflammatory bowel disease. In addition, hearing problems can predispose to falls. Early initiation of hormone replacement therapy (HRT) at the age of 11-13 years, prompt titration to the adult dose after 2 years and long-term follow-up to ensure compliance with HRT are the cornerstones of osteoporosis prevention in women with Turner syndrome.

Recognition and management of adults with Turner syndrome: From the transition of adolescence through the senior years

Turner syndrome is recognized now as a syndrome familiar not only to pediatricians and pediatric specialists, medical geneticists, adult endocrinologists, and cardiologists, but also increasingly to primary care providers, internal medicine specialists, obstetricians, and reproductive medicine specialists. In addition, the care of women with Turner syndrome may involve social services, and various educational and neuropsychologic therapies. This article focuses on the recognition and management of Turner syndrome from adolescents in transition, through adulthood, and into another transition as older women. It can be viewed as an interpretation of recent international guidelines, complementary to those recommendations, and in some instances, an update. An attempt was made to provide an international perspective. Finally, the women and families who live with Turner syndrome and who inspired several sections, are themselves part of the broad readership that may benefit from this review.

Cardiometabolic health in Turner syndrome

Individuals with Turner syndrome (TS) have a higher morbidity and mortality compared to the general population. Diabetes and cardiovascular disease are the major contributors to this burden. Precursors to diabetes and cardiovascular disease make up what is known as metabolic syndrome, including abdominal obesity, hypertension, dyslipidemia, and elevated fasting glucose. These features of poor cardiometabolic health are also prevalent among women with TS. Youth with TS also exhibit many of these features, indicating that the pathogenesis of these cardiometabolic conditions may begin early in life. The etiology of the increased risk of cardiometabolic conditions in TS is likely multifactorial, involving genetics, epigenetics, hypogonadism, medical comorbidities, medications, and lifestyle. Counseling for the increased risk of cardiometabolic diseases as well as efforts to prevent or lower this risk should be routinely provided in the care of all patients with TS. Clinical practice guidelines are now available to guide screening and treatment of cardiometabolic conditions in girls and women with TS.

New insights on diabetes in Turner syndrome: results from an observational study in adulthood

OBJECTIVE

To explore the characteristics of diabetes mellitus in adults with Turner syndrome.

DESIGN

Observational study consisting of a prospective phase after the access of adults with Turner syndrome to the Endocrinology Unit (median period of follow-up 15.6, interquartile range: 12.0-24.5 months) and a retrospective collection of data from the diagnosis of Turner syndrome until the time of access to the Endocrinology Unit. A total of 113 Italian Turner syndrome patients were included in the study. During the prospective phase of the study, each patient underwent physical examination, fasting blood sampling, and an oral glucose tolerance test on a yearly basis. Oral glucose tolerance test was used to perform the diagnosis of diabetes mellitus.

RESULTS

Before access to the Endocrinology Unit, diabetes mellitus was diagnosed in two Turner syndrome patients. Another five cases of diabetes mellitus were diagnosed at the first access to the Endocrinology Unit, whereas seven new cases of diabetes mellitus were diagnosed during the prospective phase of the study. At the diagnosis of diabetes mellitus, only one patient had fasting glucose above 126 mg/dL, and only two had an HbA1c value >6.5% (48 mmol/mol). When compared to normo-glucose tolerant patients, the diabetic patients had a significantly lower insulin-to-glucose ratio at 30 and 60 min of the oral glucose tolerance test. In the regression analyses, only age was associated with the development of diabetes mellitus.

CONCLUSIONS

This study confirms that diabetes mellitus is frequent in Turner syndrome and suggests that it is specific to the syndrome. In addition, this study demonstrates that oral glucose tolerance test is a more sensitive test than HbA1c for the diagnosis of diabetes mellitus in Turner syndrome.

Sex hormone replacement in ovarian failure - new treatment concepts

Premature ovarian failure is associated with decreased bone mass and fractures, and an increased risk of premature death from cardiovascular disease. There is also fertility compromise associated not only with the loss of ovarian function but, in those with pre-pubertal POF, inadequate uterine morphology. A wide variety of hormone replacement regimes are reported, but there is no clear evidence of best practice. Hormone replacement therapy (HRT) and the combined oral contraceptive pill (COCP) will suppress menopausal symptoms; however neither is designed to achieve physiological replacement of oestrogen and progesterone. There is evidence that physiological sex steroid replacement is superior to standard hormone replacement, in improving uterine volume as well as an improved blood pressure profile and bone mineral density. Sex steroid replacement therapy is long-term in these women, and therefore it is essential that the risk benefit ratio is optimal to maximise longer term health.

Body composition in Egyptian Turner syndrome girls

OBJECTIVE

This cross-sectional study was undertaken to construct the new body fat % curve and provide body composition reference data for adolescent girls with Turner syndrome (TS). They diagnosed cytogenetically by blood karyotyping and not treated with growth hormone (GH).

MATERIALS AND METHODS

The study included 70 TS girls from age 13 years to age 17 years. Body composition was measured by bioelectrical impedance. Smoothed centile charts were derived by using the least mean square (LMS) method.

RESULTS

The new body fat curves reflect the increase of body fat mass (FM) from age 13 years to age 17 years. Body FM % of Egyptian TS girls was lower when compared with age-matched American untreated TS girls.

CONCLUSION

This study presents the new body fat curves and reference values of body composition for untreated Egyptian TS adolescent girls. The present charts can be used for direct assessment of body FM % for Egyptian TS girls and evaluation for cases on GH treatment or other growth promoting therapy.

Metabolic effects of oral versus transdermal 17β-estradiol (E₂): a randomized clinical trial in girls with Turner syndrome

CONTEXT

The long-term effects of pure 17β-estradiol (E₂) depending on route of administration have not been well characterized.

OBJECTIVE

Our objective was to assess metabolic effects of oral vs transdermal (TD) 17β-E₂ replacement using estrogen concentration-based dosing in girls with Turner syndrome (TS).

PATIENTS

Forty girls with TS, mean age 16.7 ± 1.7 years, were recruited.

DESIGN

Subjects were randomized to 17β-E₂ orally or TD. Doses were titrated using mean E₂ concentrations of normally menstruating girls as therapeutic target. E₂, estrone (E₁), and E₁ sulfate (E₁S) were measured by liquid chromatography tandem mass spectrometry and a recombinant cell bioassay; metabolites were measured, and dual-energy x-ray absorptiometry scan and indirect calorimetry were performed.

MAIN OUTCOME

Changes in body composition and lipid oxidation were evaluated.

RESULTS

E₂ concentrations were titrated to normal range in both groups; mean oral dose was 2 mg, and TD dose was 0.1 mg. After 6 and 12 months, fat-free mass and percent fat mass, bone mineral density accrual, lipid oxidation, and resting energy expenditure rates were similar between groups. IGF-1 concentrations were lower on oral 17β-E₂, but suppression of gonadotropins was comparable with no significant changes in lipids, glucose, osteocalcin, or highly sensitive C-reactive protein between groups. However, E₁, E₁S, SHBG, and bioestrogen concentrations were significantly higher in the oral group.

CONCLUSIONS

When E₂ concentrations are titrated to the normal range, the route of delivery of 17β-E₂ does not affect differentially body composition, lipid oxidation, and lipid concentrations in hypogonadal girls with TS. However, total estrogen exposure (E₁, E₁S, and total bioestrogen) is significantly higher after oral 17β-E₂. TD 17β-E₂ results in a more physiological estrogen milieu than oral 17β-E₂ administration in girls with TS.

Individualised vs fixed dose of oral 17β-oestradiol for induction of puberty in girls with Turner syndrome: an open-randomised parallel trial

CONTEXT

Oestrogen induction of pubertal changes in Turner girls may reinforce their psychological well-being and may also optimise final height; however, oestrogen type, dose, and route are not well established.

OBJECTIVE

To induce normal pubertal development in Turner girls and ovarian insufficiency with oral 17β-oestradiol (E(2)), either as individualised dose (ID) or as fixed dose (FD), and to determine whether growth is affected.

DESIGN

Open-label randomised, parallel groups, multicentre clinical trial in 48 GH-treated Turner girls. Oral E(2) was given in tablets, either as an ID of 5-15 μg/kg per day during 2 years or as a FD of 0.2 mg daily during the first year followed by 0.5 mg daily during the second year. Main outcome measures were the event of attaining a Tanner breast staging ≥4 (primary), FSH, and auxological variables (secondary).

RESULTS

Shorter median time to Tanner staging ≥ B4 in the FD group (733 days) compared with the ID group (818 days) (P=0.046). Higher proportion of girls with Tanner staging ≥ B4 (65%) in the FD group compared with the ID group (42%) (P=0.068). Bone age did not show inadequate acceleration and adult height prediction was maintained in both groups. No oestrogen-related adverse events were reported.

CONCLUSIONS

Two-year treatment with oral E(2) can progressively induce normal pubertal development in Turner syndrome. Low-dose oral E(2) given as a FD produces a satisfactory pubertal development not inferior to ID. Treatment was well tolerated and did not interfere with the growth-promoting effect of GH.

Clinical profile of coexisting conditions in type 1 diabetes mellitus patients

AIMS

Type 1 diabetes mellitus (T1DM) is associated with various genetic and autoimmune diseases implicated in its etiopathogenesis. We hereby profile the clinical association of such diseases among patients from our center.

METHODS

Consecutive patients of T1DM presenting to department of Endocrinology from May 1997 to December 2011 were retrospectively analyzed in context of associated clinical profile.

RESULTS

Among 260 patients diagnosed as T1DM, 21 (8%) had hypothyroidism, 4 (1.5%) had hyperthyroidism and 2 (0.7%) had primary adrenal insufficiency. Eighteen patients (7%) had celiac disease, 9 (3.5%) had Turner's syndrome, 5 patients (1.9%) had Klinefelter's syndrome, whereas Down's syndrome and Noonan's syndrome was present in 2 and 1 patients (0.7%) respectively. One patient had Wolframs' syndrome and 1 patients had myasthenia gravis. Systemic lupus erythematosus and rheumatoid arthritis were present in 3 and 1 patients respectively. Total of 5 patients with cerebral palsy, 4 cases with deaf mutism, 4 cases with acute psychosis and 16 patients with depression were noted. Mean age of study patients was 20.8±9.8 years (range, 3-23 years).

CONCLUSION

Various conditions including genetic (Down, Turner, Noonan, and Klinefelter's), autoimmune (thyroid and adrenal disorders, myasthenia gravis, SLE, rheumatoid arthritis) and central nervous system diseases were the associated diseases encountered in our patients. Routine screening is required for early diagnosis and treatment of associated co morbidities.

Pharmacokinetics and pharmacodynamics of oral and transdermal 17β estradiol in girls with Turner syndrome

CONTEXT

The type, dose, and route of 17β-estradiol (E(2)) used to feminize girls with Turner syndrome (TS) is not well established.

OBJECTIVE

The objective of the study was to characterize pharmacokinetics and pharmacodynamics of oral vs. transdermal E(2).

SETTING

The study was conducted at a clinical research center.

SUBJECTS

Ten girls with TS, mean age 17.7 ± 0.4 (se) yr and 20 normally menstruating controls (aged 16.8 ± 0.4 yr) participated in the study.

INTERVENTIONS

TS subjects were randomized 2 wk each to: low-dose daily oral (0.5 mg) and biweekly transdermal E(2) (0.0375 mg) with 2 wk washout in between or high-dose oral (2.0 mg) and transdermal (0.075 mg), studied for 24 h each. Tandem mass spectrometry E(2) and estrone (E(1)) assays and a recombinant cell bioassay were used.

RESULTS

Controls consisted of the following: E(2), 96 ± 11 pg/ml (se), E(1), 70 ± 7 (mean follicular/luteal). TS consisted of the following: E(2), average concentration on low-dose oral, 18 ± 2.1 pg/ml, low-dose transdermal, 38 ± 13, high-dose oral, 46 ± 15, high-dose transdermal, 114 ± 31 pg/ml. E(1) concentrations were much higher on oral E(2) (low or high dose) than transdermal in TS and higher than controls. Bioestrogen was closest to normal in the high-dose transdermal group. LH and FSH decreased more in transdermal than oral low-dose routes and similarly in the high-dose oral and transdermal groups. IGF-I concentrations were variable (P = NS) among groups, and low-density lipoprotein/high-density lipoprotein cholesterol responses were variable.

CONCLUSIONS

Transdermal E(2) results in E(2), E(1), and bioestrogen concentrations closer to normal and achieves greater suppression of LH/FSH in lower doses compared with normal. Whether the long-term metabolic effects of estrogen differ using the same form of E(2), depending on route, awaits further study in TS.

Physiological versus standard sex steroid replacement in young women with premature ovarian failure: effects on bone mass acquisition and turnover

BACKGROUND

The aim of this exploratory study was to establish whether we could improve skeletal health with a physiological regimen of SSR in young women with premature ovarian failure (POF).

PATIENTS AND METHODS

In an open-label randomized controlled crossover trial, 34 women with POF were randomized to 4-week cycles of pSSR (transdermal oestradiol, 100 μg daily for week 1, 150 μg for weeks 2-4; vaginal progesterone, 200 mg twice daily for weeks 3-4) or standard hormone replacement treatment (sHRT) (oral ethinyloestradiol 30 μg and 1·5 mg norethisterone daily for weeks 1-3, week 4 'pill-free') for 12 months. Bone mineral density (BMD) was measured by DEXA at study entry and after each 12-month treatment period. Blood samples for hormones and markers of bone formation (bone alkaline phosphatase, BALP and type I collagen N-terminal propeptide, PINP) and bone resorption (CrossLaps) were collected pre-/postwashout and after 3, 6 and 12 months of each treatment.

RESULTS

Eighteen women, mean 27 (range 19-39) years, completed the study. Both regimens caused similar suppression of LH and FSH. Mean baseline lumbar spine BMD z-score was -0·89 (95% CI -1·27 to -0·51) and increased by +0·17 (CI +0·07 to +0·27) in response to pSSR (P = 0·003), compared with +0·07 (CI -0·03 to +0·18) during standard HRT (P = 0·2). During pSSR, the increment in lumbar spine BMD z-score was related positively to oestradiol (r = +0·49, P = 0·04) and inversely to FSH (r = -0·65, P = 0·004). Bone formation markers, BALP and P1NP increased in the pSSR arm (anova P < 0·001) but decreased in the sHRT arm (P < 0·01). Both treatments suppressed the bone resorption marker, CrossLaps (P < 0·001).

CONCLUSION

We conclude that pSSR over 12 months has a beneficial affect on bone mass acquisition on the lumbar spine in women with POF, mediated by increased bone formation and decreased bone resorption.

Turner syndrome and the evolution of human sexual dimorphism

Turner syndrome is caused by loss of all or part of an X chromosome in females. A series of recent studies has characterized phenotypic differences between Turner females retaining the intact maternally inherited versus paternally inherited X chromosome, which have been interpreted as evidence for effects of X-linked imprinted genes. In this study I demonstrate that the differences between Turner females with a maternal X and a paternal X broadly parallel the differences between males and normal females for a large suite of traits, including lipid profile and visceral fat, response to growth hormone, sensorineural hearing loss, congenital heart and kidney malformations, neuroanatomy (sizes of the cerebellum, hippocampus, caudate nuclei and superior temporal gyrus), and aspects of cognition. This pattern indicates that diverse aspects of human sex differences are mediated in part by X-linked genes, via genomic imprinting of such genes, higher rates of mosaicism in Turner females with an intact X chromosome of paternal origin, karyotypic differences between Turner females with a maternal versus paternal X chromosome, or some combination of these phenomena. Determining the relative contributions of genomic imprinting, karyotype and mosaicism to variation in Turner syndrome phenotypes has important implications for both clinical treatment of individuals with this syndrome, and hypotheses for the evolution and development of human sexual dimorphism.

Metabolic effects of oral versus transdermal estrogen in growth hormone-treated girls with turner syndrome

BACKGROUND

Transdermal (TD) estrogen is often preferred over the oral route in postmenopausal and GH-deficient women taking estrogen, but this has not been studied in detail in girls.

OBJECTIVE

Our objective was to study the metabolic effects of oral vs. TD estrogen in GH-treated girls with Turner syndrome.

DESIGN AND METHODS

Eleven girls with Turner syndrome, mean age 13.4 +/- 0.5 (se) yr, on GH for at least 6 months were recruited. Studies included [(13)C]leucine and d5-glycerol infusions, indirect calorimetry, dual-emission x-ray absorptiometry, and hormone and substrate measurements. They received, in random order, 17beta-estradiol orally (0.5, 1, and 2 mg for 2 wk each) and TD (0.025, 0.0375, and 0.05 mg for 2 wk each), and studies were repeated after each 6-wk course with 4 wk washout in between.

RESULTS

Rates of whole-body protein turnover, oxidation and synthesis, lipolysis, lipid and carbohydrate oxidation, and resting energy expenditure were unaffected by either form of estrogen; nor were lipids, insulin, and fibrinogen concentrations affected. Plasma IGF-I concentrations did not change clinically significantly with either form of estrogen, despite higher estrogen concentrations after oral estrogen. Estradiol concentrations did not correlate with any variables measured.

CONCLUSIONS

In GH-treated girls with Turner syndrome, neither oral nor TD estrogen adversely affected rates of protein turnover, lipolysis, and lipid oxidation rates or plasma lipids, fibrinogen, or fasting insulin concentrations. There was no clinically significant change in IGF-I concentrations after either form of estrogen. In aggregate, these data suggest that the route of delivery of estrogen does not adversely affect these metabolic effects of GH in young girls with Turner syndrome.

Protein metabolism in Turner syndrome and the impact of hormone replacement therapy

BACKGROUND

Studies have documented an altered body composition in Turner syndrome (TS). Body fat is increased and muscle mass is decreased. Ovarian failure necessitates substitution with female hormone replacement therapy (HRT), and HRT induces favourable changes in body composition. It is unknown how HRT affects protein metabolism.

AIM

To test whether alterations in body composition before and after HRT in TS are a result of altered protein metabolism.

DESIGN

We performed a randomized crossover study with active treatment (HRT in TS and oral contraceptives in controls) or no treatment.

MATERIALS AND METHODS

We studied eight women (age 29.7 +/- 5.6 (mean +/- SD) years) with TS, verified by karyotype, and eight age-matched controls (age 27.3 +/- 4.9 years). All subjects underwent a 3-h study in the postabsorptive state. Protein dynamics of the whole body and of the forearm muscles were measured by an amino acid tracer dilution technique using [(15)N]phenylalanine and [(2)H(4)]tyrosine. Substrate metabolism was examined by indirect calorimetry.

RESULTS

Energy expenditure was comparable among TS and controls, and did not change during active treatment. Whole-body phenylalanine and tyrosine fluxes were similar in the untreated situations, and did not change during active treatment. Amino acid degradation and protein synthesis were similar in all situations. Muscle protein breakdown was similar among groups, and was not affected by treatment. Muscle protein synthesis rate and forearm blood flow did not differ among groups or due to treatment.

CONCLUSION

Protein metabolism in TS is comparable to controls, and is not affected by HRT.

Effects of Growth Hormone on Growth, Insulin Resistance and Related Hormones (Ghrelin, Leptin and Adiponectin) in Turner Syndrome

BACKGROUND

Concomitant evaluation of the metabolic and growth-promoting effects of growth hormone (GH) therapy in Turner syndrome (TS) may be used in the prediction of the growth response to GH therapy.

AIM

To evaluate the metabolic effects of GH therapy in TS and correlation with the short-term growth response.

PATIENTS

24 prepubertal children with TS, aged 9.4 +/- 2.6 years were followed for auxology and IGF-I, IGFBP-3, leptin, ghrelin, adiponectin, lipids and OGTT results in a prospective multicenter study.

INTERVENTION

GH (Genotropin) in a dose of 50 microg/kg/day for 1 year.

RESULTS

Height standard deviation score (SDS) increased from -3.9 +/- 1.5 to -3.5 +/- 1.4 (p = 0.000) on therapy. BMI did not change. IGF-I SDS increased from -2.3 +/- 0.4 to -1.6 +/- 1.1 at 3 and 6 months (p = 0.001) and decreased thereafter. Serum leptin decreased significantly from 2.3 +/- 3.9 to 1.7 +/- 5.3 ng/ml (p = 0.022) at 3 months and increased afterwards. Serum ghrelin decreased from 1.2 +/- 0.8 to 0.9 +/- 0.4 ng/ml (p = 0.005) with no change in adiponectin. Basal and stimulated insulin levels also increased significantly. Delta height SDS over 1 year showed a significant correlation with Delta IGF-I(0-3 months) (r = 0.450, p = 0.027).

CONCLUSION

IGF-I may be considered as a marker of growth response in TS at short term. Leptin shows a decrease at short term but does not have a correlation with growth response. The decrease in ghrelin in face of unchanged weight seems to be associated with increase in IGF-I and insulin levels. The unchanged adiponectin levels in spite of an increase in insulin levels indicates that adiponectin is mainly affected by weight, not insulin.

Clinical practice in Turner syndrome

Turner syndrome (TS) is a common genetic disorder, resulting from the partial or complete absence of one sex chromosome, and occurring in approximately 50 per 100,000 liveborn girls. TS is associated with reduced adult height and with gonadal dysgenesis, leading to insufficient circulating levels of female sex steroids and to infertility. Morbidity and mortality are increased in TS but average intellectual performance is within the normal range. A number of recent studies have allowed new insights to be gained with respect to epidemiology, genetics, cardiology, endocrinology and metabolism. Elucidation of the effects of short stature homeobox protein deficiency has explained some of the phenotypic characteristics in TS, principally short stature. Treatment with growth hormone during childhood and adolescence allows a considerable gain in adult height, although the consequences of this treatment in the very long term are not clear. Puberty must be induced in most cases, and female sex hormone replacement therapy (HRT) is given during adult years. The optimal dose of HRT has not been established and, likewise, the benefits and drawbacks of HRT have not been thoroughly evaluated. The risks of type 2 diabetes, type 1 diabetes, hypothyroidism, osteoporosis, congenital heart disease, hypertension, ischemic heart disease, aortic dilatation and dissection, inflammatory bowel disease and celiac disease are clearly elevated, and proper care during adulthood is important. Currently no firm guidelines for diagnosis exist. In conclusion, TS is a condition associated with a number of diseases and conditions that are reviewed in the present paper. Individuals with TS need life-long medical attention.

Turner syndrome: an update and review for the primary pediatrician

Turner syndrome (TS) is among the most common of the sex chromosomal aneuploidies. It results from the absence of one sex chromosome (or part of an X chromosome) in a female, leaving only one X chromosome present in the cell. Primary care physicians should be able to recognize the presenting signs and symptoms of TS, and once the diagnosis is confirmed by a chromosome analysis, they should be able to serve as a valuable source of support for the patient and her family and understand the most current treatments available.

Nocturnal hypertension and impaired sympathovagal tone in Turner syndrome

OBJECTIVE

Increased blood pressure (BP), night: day BP ratio, and heart rate is seen in Turner syndrome (TS), and an increased risk of ischaemic heart disease and type 2 diabetes, as well as aortic dilatation and dissection. We hypothesized that altered heart rate variability is present in TS in comparison with controls, and can be influenced by hormonal replacement therapy (HRT).

MATERIAL AND METHODS

We examined the impact of HRT on sympathovagal control of heart rate variability. Patients (n = 8, aged 29.5 +/- 5.3 years; no treatment or HRT) and controls (n = 8, aged 28.5 +/- 4.2 years; no treatment) were examined by short-term spectral analysis (supine-standing), bedside neuropathy tests, and 24-h ambulatory BP. N-terminal pro-brain natriuretic peptide (BNP), renin, aldosterone and urinary albumin excretion was determined. The interaction between position and status (TS or control) was examined for data from spectral analysis.

RESULTS

Low-frequency (LF) power, coefficient of component variation of LF (both measures of sympathetic and vagal activity), and the LF: high-frequency (HF) power ratio (a measure of sympathovagal balance) were diminished in TS compared with controls, especially during standing. Systolic and diastolic night ambulatory BP (both P = 0.03), and systolic and diastolic night: day ratio (P = 0.01; P = 0.004) was increased in TS. During HRT diastolic day (P = 0.05) and 24-h diastolic ambulatory BP (P = 0.08) decreased. N-terminal pro-BNP was elevated in TS.

CONCLUSION

Decreased sympathovagal balance or tone and nocturnal hypertension is present in TS, and N-terminal pro-BNP is elevated. HRT did not modulate the sympathovagal tone, but decreased BP. These changes may be linked to the increased cardiovascular risk and possibly the increased risk of aortic dilatation in TS.